A relay protection fault identification and response system

Abstract

The present invention relates to the technical field of electrical fault identification and response, and specifically relates to a relay protection fault identification and response system. The system includes a fault propagation path tracking module, a regional fault monitoring module, a misoperation cumulative effect calculation module, a protection level adjustment module, and a fault response module. In the present invention, based on the triggering sequence and triggering interval time of relay protection devices, the misoperation propagation mode is extracted, the cascaded misoperation associated devices are screened, combined with the regional power grid fault risk score, the protection level setting is optimized, the misoperation cumulative trend is calculated through the misoperation triggering frequency, the high misoperation devices are identified, the protection level adjustment factor is calculated, the relay protection level is optimized according to the power grid state, so that the protection strategy adapts to different operating conditions, the power grid operation state parameters are calculated in combination with the adjusted protection level, the stability change is analyzed, the relay protection response strategy is optimized, so that the relay protection system has the ability of adaptive adjustment, and the influence range of sudden faults is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical fault identification and response, and particularly to a relay protection fault identification and response system. Background Art

[0002] The technical field of electrical fault identification and response involves the monitoring, analysis, and fault detection of the operation status of power systems and their equipment, and quickly responds when abnormalities occur. It is widely used in scenarios such as substations, power grid dispatching, and industrial distribution systems, aiming to improve the reliability and security of the power supply system. It mainly includes key links such as fault detection, fault location, protection action triggering, alarm, and information transmission. Relying on sensors, intelligent algorithms, and communication technologies, it realizes the real-time monitoring and processing of abnormal situations such as short circuits, overloads, and grounding faults. With the development of smart grids, this field continuously introduces artificial intelligence, big data analysis, and Internet of Things technologies to improve the accuracy and response speed of fault diagnosis.

[0003] Among them, the relay protection fault identification and response system is an intelligent monitoring and emergency response system for relay protection devices. It can automatically detect the operation status of relay protection devices, identify relay protection abnormalities caused by misoperation, refusal to operate, or hardware failures, and quickly respond to reduce power grid accidents caused by protection failures. Its core functions include relay protection status monitoring, fault mode identification, real-time alarm, and emergency treatment strategy execution, which can effectively improve the stability and security of the power system.

[0004] The existing technology mainly relies on a single fault detection parameter and lacks an effective analysis of the propagation mode of relay protection misoperation. When cascaded misoperations occur, it is difficult to identify their influence range, resulting in continuous misoperations of multiple devices and affecting the stability of the power grid. The short-term fault monitoring method for regional power grids is based on fixed thresholds and fails to comprehensively evaluate by combining the real-time current impact intensity and voltage fluctuation amplitude, resulting in inaccurate judgment of some high-risk areas and mismatched relay protection response strategies. The cumulative assessment of misoperations is based on the historical misoperation records of a single device and does not consider the mutual influence between devices, making it difficult to identify the impact of misoperation accumulation on the overall power grid. This leads to frequent misoperations of individual devices without triggering adjustments, and the protection level cannot be adjusted according to the actual power grid state, resulting in delayed or mis-triggered protection actions in scenarios with large load fluctuations or frequent short-term shocks, affecting the reliability and accuracy of the relay protection system. Summary of the Invention

[0005] The purpose of the present invention is to solve the deficiencies existing in the prior art and propose a relay protection fault identification and response system.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions: A relay protection fault identification and response system includes:

[0007] The fault propagation path tracking module collects the data of relay protection devices, records the triggering sequence of relay protection devices, calculates the triggering interval time, analyzes the misoperation propagation path, calculates the correlation strength of cascading misoperations, judges cascading misoperations and classifies the devices, and generates relay protection misoperation propagation data;

[0008] Based on the relay protection misoperation propagation data, the regional fault monitoring module obtains the regional power grid data, calculates the occurrence frequency of regional power grid faults, and generates the regional fault risk classification result;

[0009] According to the relay protection misoperation propagation data and the regional fault risk classification result, the misoperation cumulative effect calculation module calculates the cumulative trend of relay protection misoperations, extracts the misoperation triggering frequency, and outputs the relay protection misoperation cumulative strength data;

[0010] According to the relay protection misoperation cumulative strength data and the regional fault risk classification result, the protection level adjustment module calculates the protection level adjustment factor of the relay protection device and generates the set result of the relay protection level after adjustment;

[0011] Based on the set result of the relay protection level after adjustment, the fault response module calculates the operation state parameters of the regional power grid, dynamically optimizes the relay protection adjustment measures, and generates the dynamic response plan for the power grid relay protection.

[0012] As a further solution of the present invention, the relay protection misoperation propagation data includes the recording of the triggering time of relay protection devices, the recording of current mutation rate, the recording of voltage drop rate, the triggering sequence of relay protection devices, the triggering interval time of relay protection devices, the correlation strength of cascading misoperations, the misoperation triggering frequency of relay protection, the grading result of the cumulative influence value of misoperations, and the misoperation propagation path of relay protection; the regional fault risk classification result includes the short-term fault triggering statistics of the regional power grid, the voltage fluctuation amplitude distribution, the current impact intensity distribution, the fault occurrence frequency per unit time, the regional power grid fault risk score, and the screening result of high-risk areas; the relay protection misoperation cumulative strength data includes the cumulative trend of relay protection misoperations, the statistical result of the misoperation triggering frequency of relay protection devices, the cumulative strength of relay protection device misoperations, and the screening result of high-risk misoperation devices; the set result of the relay protection level after adjustment includes the protection level adjustment factor of the relay protection device, the determination result of the relay protection level adjustment, and the protection level of the relay protection device after adjustment; the dynamic response plan for the power grid relay protection specifically refers to the operation state parameters of the regional power grid after adjustment, the record of the difference analysis of the operation stability of the regional power grid, and the optimization plan of the relay protection adjustment measures.

[0013] As a further solution of the present invention, the fault propagation path tracking module includes a relay protection device trigger data collection sub-module, a relay protection misoperation propagation analysis sub-module, and a relay protection misoperation impact assessment sub-module;

[0014] The relay protection device trigger data collection sub-module collects the current mutation rate and voltage drop rate according to the trigger moment of the relay protection device, records the trigger sequence of the relay protection device, calculates the trigger interval time between adjacent relay protection devices, and obtains the trigger timing data of the relay protection device;

[0015] The relay protection misoperation propagation analysis sub-module analyzes the relay protection misoperation propagation path according to the trigger timing data of the relay protection device, screens the devices with the trigger interval time between relay protection devices less than the set trigger threshold, and uses the formula:

[0016] ;

[0017] Calculate the cascading misoperation correlation strength and judge the cascading misoperation to obtain the cascading misoperation propagation sequence, where represents the th trigger moment of the relay protection device, represents the th trigger moment of the relay protection device, represents the set trigger threshold, represents the total number of devices in the relay protection device trigger sequence;

[0018] The relay protection misoperation impact assessment sub-module calculates the trigger frequency of the relay protection misoperation according to the cascading misoperation propagation sequence, classifies the devices according to the cumulative impact value of the misoperation, screens the relay protection devices with the cumulative impact value of the misoperation exceeding the set interval, and generates the relay protection misoperation propagation data.

[0019] As a further solution of the present invention, the regional fault monitoring module includes a power grid fault data collection sub-module, a regional fault risk calculation sub-module, and a regional fault risk classification sub-module;

[0020] The power grid fault data collection sub-module collects the short-term fault trigger times, voltage fluctuation amplitudes, and current impact intensities of the regional power grid based on the relay protection misoperation propagation data, calculates the regional power grid fault occurrence frequency per unit time, and obtains the regional power grid fault characteristic data;

[0021] The regional fault risk calculation sub-module calls the regional power grid fault characteristic data, calculates the regional power grid fault risk score according to the fault occurrence rate, voltage stability, and current impact characteristics, and uses the formula:

[0022] ;

[0023] Calculate the fault risk score of the regional power grid , and obtain the regional power grid fault risk assessment result, where represents the number of faults occurring within the ith time period, represents the unit time length, represents the voltage value in the ith time period, represents the reference voltage value, represents the current impact intensity in the ith time period, represents the total number of calculation time periods;

[0024] The regional fault risk classification sub-module screens out the risk areas with fault risk scores higher than the set risk threshold according to the regional power grid fault risk assessment result, marks them as high-risk areas, and generates the regional fault risk classification result.

[0025] As a further solution of the present invention, the maloperation cumulative effect calculation module includes a relay protection maloperation cumulative trend calculation sub-module, a relay protection maloperation cumulative intensity calculation sub-module, and a relay protection maloperation high-risk screening sub-module;

[0026] The relay protection maloperation cumulative trend calculation sub-module extracts the maloperation trigger frequency of the relay protection device based on the relay protection maloperation propagation data and the regional fault risk classification result, calculates the cumulative change amount of the maloperation frequency in the time dimension, and obtains the relay protection maloperation cumulative trend record;

[0027] The relay protection maloperation cumulative intensity calculation sub-module uses the formula according to the relay protection maloperation cumulative trend record:

[0028] ;

[0029] Calculate the cumulative intensity of the relay protection device maloperation , and obtain the relay protection maloperation cumulative intensity data, where represents the maloperation trigger frequency in the th time period, represents the unit time interval, represents the maloperation propagation influence degree in the th time period, represents the average maloperation propagation influence degree of all time periods, , represents the weight factor of the relay protection device, represents the total number of relay protection devices, represents the total number of calculation time periods;

[0030] The high-risk screening sub-module for maloperation of relay protection screens relay protection devices with maloperation cumulative intensity exceeding the set cumulative threshold based on the maloperation cumulative intensity data of relay protection, and generates a list of high-risk devices for maloperation of relay protection.

[0031] As a further solution of the present invention, the protection level adjustment module includes a relay protection device adjustment factor calculation sub-module, a relay protection device adjustment screening sub-module, and a relay protection device level setting sub-module;

[0032] The relay protection device adjustment factor calculation sub-module is based on the maloperation cumulative intensity data of relay protection and the regional fault risk classification result, and uses the formula:

[0033] ;

[0034] Calculate the protection level adjustment factor of the relay protection device , and obtain the relay protection device adjustment factor data, where represents the maloperation cumulative intensity in the th time period, represents the unit time length, represents the regional fault risk score in the th time period, represents the median regional fault risk score of all time periods, represents the voltage fluctuation amplitude of the th relay protection device within the time period, represents the reference voltage fluctuation amplitude, represents the weight factor of the relay protection device, represents the total number of relay protection devices, represents the total number of calculation time periods, is a small constant to prevent the denominator from being zero;

[0035] The relay protection device adjustment screening sub-module screens relay protection devices with protection level adjustment factors exceeding the set adjustment threshold according to the relay protection device adjustment factor data, and obtains a relay protection device adjustment list;

[0036] The relay protection device level setting sub-module adjusts the protection level of the corresponding relay protection device based on the relay protection device adjustment list, and generates a set result of the adjusted relay protection level.

[0037] As a further solution of the present invention, the fault response module includes a relay protection adjustment sub-module, a regional power grid status calculation sub-module, and a power grid stability optimization sub-module;

[0038] The relay protection adjustment sub-module records the adjusted protection action time, setting value, and tripping threshold value based on the set result of the relay protection level after adjustment, compares the change range of the relay protection action time before and after adjustment, screens key relay protection adjustment points, calls the key relay protection adjustment points to match with the protection fault data, calculates the deviation of the relay protection response duration after adjustment, and obtains the relay protection response deviation amount.

[0039] Based on the relay protection response deviation amount, the regional power grid status calculation sub-module combines the voltage stability, frequency fluctuation range, and load transfer efficiency, compares the change trend of the power grid operation parameters before and after adjustment, and uses the formula:

[0040] ;

[0041] Calculate the change amount of the power grid operation status , compare the change intervals of the operation parameters before and after adjustment, and obtain the power grid operation status parameters after adjustment, where represents the voltage value at time i after adjustment, represents the voltage value at time i - 1 before adjustment, represents the relay protection response time at time i, represents the active power at time i after adjustment, represents the reactive power at time i after adjustment, represents the frequency at time i after adjustment, represents the reference frequency, represents the total number of calculation periods;

[0042] Based on the power grid operation status parameters after adjustment, the power grid stability optimization sub-module calculates the change trend of the power grid stability, screens key factors affecting the operation status change, optimizes the relay protection adjustment strategy, adjusts the setting of the relay protection level, corrects the relay protection tripping threshold, and establishes a dynamic response plan for the power grid relay protection.

[0043] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0044] In the present invention, based on the triggering sequence and triggering interval time of the relay protection device, the misoperation propagation mode is extracted, the cascaded misoperation associated devices are screened, combined with the regional power grid fault risk score, the protection level setting is optimized, the cumulative trend of misoperation is calculated through the misoperation triggering frequency, the high misoperation devices are identified, the protection level adjustment factor is calculated, the relay protection level is optimized according to the power grid status, so that the protection strategy adapts to different operating conditions, calculates the power grid operation status parameters in combination with the adjusted protection level, analyzes the stability change, optimizes the relay protection response strategy, enables the relay protection system to have the ability of adaptive adjustment, and reduces the influence range of sudden faults. Brief Description of the Drawings

[0045] Figure 1 is the system flow chart of the present invention;

[0046] Figure 2 is the flow chart of the fault propagation path tracing module of the present invention;

[0047] Figure 3 is the flow chart of the regional fault monitoring module of the present invention;

[0048] Figure 4 is the flow chart of the misoperation cumulative effect calculation module of the present invention;

[0049] Figure 5 is the flow chart of the protection level adjustment module of the present invention;

[0050] Figure 6 is the flow chart of the fault response module of the present invention. Specific Embodiments

[0051] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0052] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. In addition, in the description of the present invention, the meaning of "a plurality of" is two or more unless otherwise specifically defined.

[0053] Please refer to Figure 1 , a relay protection fault identification and response system includes:

[0054] The fault propagation path tracing module collects data on the triggering time, current mutation rate, and voltage drop rate of the relay protection device, records the triggering sequence of the relay protection device, calculates the triggering interval time between adjacent relay protection devices, analyzes the misoperation propagation path of the relay protection, screens the devices with a triggering interval time between relay protection devices less than the set triggering threshold, calculates the cascade misoperation correlation strength, determines the cascade misoperation, calculates the triggering frequency of the relay protection misoperation, classifies the devices according to the cumulative influence value of the misoperation, screens the relay protection devices with a cumulative influence value of the misoperation exceeding the set interval, and generates relay protection misoperation propagation data;

[0055] The regional fault monitoring module collects the short-term fault trigger times, voltage fluctuation amplitudes, and current impact intensity data of the regional power grid based on the relay protection misoperation propagation data, calculates the fault occurrence frequency of the regional power grid per unit time, calculates the regional power grid fault risk score based on the fault incidence rate, voltage stability, and current impact characteristics, screens the high-risk areas where the regional power grid fault risk score is higher than the set risk threshold, and generates the regional fault risk classification result;

[0056] The misoperation cumulative effect calculation module calculates the cumulative trend of relay protection misoperation according to the relay protection misoperation propagation data and the regional fault risk classification result, extracts the misoperation trigger frequency of the relay protection device, calculates the cumulative intensity of the relay protection device misoperation, outputs the cumulative intensity data of the relay protection device misoperation, and screens the high-risk misoperation devices where the cumulative misoperation of the relay protection device exceeds the set cumulative threshold;

[0057] The protection level adjustment module calculates the protection level adjustment factor of the relay protection device according to the cumulative intensity data of the relay protection device misoperation and the regional fault risk classification result, screens the relay protection devices whose protection level adjustment factor exceeds the set adjustment threshold, and adjusts the protection level of the corresponding relay protection device to generate the set result of the relay protection level after adjustment;

[0058] The fault response module calculates the operating state parameters of the regional power grid after adjustment based on the set result of the relay protection level after adjustment, analyzes the difference in the operating stability of the regional power grid before and after adjustment, dynamically optimizes the relay protection adjustment measures, and generates the dynamic response plan for the power grid relay protection.

[0059] The relay protection misoperation propagation data includes the trigger time record of the relay protection device, the current mutation rate record, the voltage drop rate record, the trigger sequence of the relay protection device, the trigger interval time of the relay protection device, the cascade misoperation correlation intensity, the misoperation trigger frequency of the relay protection device, the grading result of the cumulative misoperation impact value, and the relay protection misoperation propagation path; the regional fault risk classification result includes the short-term fault trigger statistics of the regional power grid, the voltage fluctuation amplitude distribution, the current impact intensity distribution, the fault occurrence frequency per unit time, the regional power grid fault risk score, and the high-risk area screening result; the cumulative intensity data of the relay protection device misoperation includes the cumulative trend of the relay protection device misoperation, the statistical result of the misoperation trigger frequency of the relay protection device, the cumulative intensity of the relay protection device misoperation, and the screening result of the high-risk misoperation devices; the set result of the relay protection level after adjustment includes the protection level adjustment factor of the relay protection device, the judgment result of the relay protection device protection level adjustment, and the protection level of the relay protection device after adjustment; the dynamic response plan for the power grid relay protection specifically refers to the operating state parameters of the regional power grid after adjustment, the record of the analysis of the difference in the operating stability of the regional power grid, and the optimization plan for the relay protection adjustment measures.

[0060] Please refer to Figure 2, the fault propagation path tracking module includes a relay protection device trigger data collection sub-module, a relay protection misoperation propagation analysis sub-module, and a relay protection misoperation impact assessment sub-module;

[0061] The relay protection device trigger data collection sub-module collects the current mutation rate and voltage drop rate according to the trigger time of the relay protection device, records the trigger sequence of the relay protection device, calculates the trigger interval time between adjacent relay protection devices, and obtains the trigger timing data of the relay protection device;

[0062] Based on the trigger time of the relay protection device, the trigger timing information of the relay protection device in the system is collected, specifically including the current mutation rate and voltage drop rate of the device when a fault occurs. In actual applications, multiple relay protection devices in a substation operate together. When a short circuit or overload fault occurs in a certain component of the system, the corresponding relay protection device will be triggered. After the trigger, the trigger time of the relay protection device is recorded. For example, the trigger time of the relay protection device of a certain line is , and the trigger time of the relay protection device of the adjacent line is . By calculating the time difference between the triggers of adjacent devices, the cascade relationship between the devices is determined. The current mutation rate is calculated from the current change before and after the fault. For example, the current of a certain line before the fault is , and the current increases to after the fault. Then its current mutation rate is:

[0063] ;

[0064] Similarly, the calculation method of the voltage drop rate is:

[0065] ;

[0066] Among them, is the voltage before the fault, is the voltage after the fault. If the voltage before the fault is 220 kV and drops to 180 kV after the fault, the voltage drop rate is:

[0067] ;

[0068] All data such as the trigger time, trigger timing, trigger interval time between adjacent relay protection devices, corresponding current mutation rate, voltage drop rate, etc. of all relay protection devices are recorded in the database to form the trigger timing data of the relay protection device.

[0069] The relay protection misoperation propagation analysis sub-module analyzes the relay protection misoperation propagation path according to the trigger timing data of the relay protection device, screens the devices with the trigger interval time between relay protection devices less than the set trigger threshold, and uses the formula:

[0070] ;

[0071] Calculate the correlation strength of cascaded maloperations , and judge the cascaded maloperation to obtain the cascaded maloperation propagation sequence, where represents the th trigger time of the relay protection device, represents the th trigger time of the relay protection device, represents the set trigger threshold, represents the total number of devices in the trigger sequence of the relay protection device;

[0072] Call the trigger time series data of the relay protection device, analyze the misoperation propagation path of each relay protection device, and judge whether the misoperation of a certain relay protection device will cause the misoperation of subsequent devices according to the trigger time series of adjacent relay protection devices. In practical applications, if the trigger time of relay protection device A on a certain line is 0.15 s, and the trigger time of its adjacent device B is 0.22 s, then the trigger interval between device A and B is 0.07 s. If the set trigger threshold is 0.1 s, the judgment condition for misoperation propagation is satisfied, and the correlation strength of cascaded maloperations is calculated using the formula.

[0073] Let , , , , , and the calculation result is:

[0074] ;

[0075] If the set misoperation propagation threshold is 0.5, and the current calculated value is greater than 0.5, it is determined that a cascaded maloperation has occurred, and the cascaded maloperation propagation sequence is obtained.

[0076] The relay protection misoperation impact assessment sub-module calculates the misoperation trigger frequency of the relay protection according to the cascaded misoperation propagation sequence, classifies the devices based on the cumulative misoperation impact value, screens the relay protection devices whose cumulative misoperation impact value exceeds the set interval, and generates relay protection misoperation propagation data;

[0077] Call the cascaded misoperation propagation sequence, count the number of misoperations of each relay protection device within a certain period of time, calculate the misoperation trigger frequency. For example, if a certain device has 4 misoperations within 10 minutes, then the misoperation trigger frequency is times / minute, and calculate the cumulative misoperation impact value according to this value. The calculation method of the impact value is:

[0078] ;

[0079] where is the cumulative misoperation impact value, is the cascaded maloperation correlation strength, is the maloperation trigger frequency, substituting the aforementioned calculated value , times / minute, and the calculation gives:

[0080] ;

[0081] Calculate the cumulative impact value of maloperation for all relay protection devices, and set the maloperation classification threshold. Set the cumulative impact value of maloperation less than 0.2 level as low impact, 0.2 to 0.5 as medium impact, and greater than 0.5 as high impact. The calculated value of 0.212 belongs to the medium impact level. Screen out the relay protection devices whose impact values exceed the set range, and generate the relay protection maloperation propagation data.

[0082] Please refer to Figure 3 , the regional fault monitoring module includes a power grid fault data collection sub-module, a regional fault risk calculation sub-module, and a regional fault risk classification sub-module;

[0083] Based on the relay protection maloperation propagation data, the power grid fault data collection sub-module collects the short-time fault trigger times, voltage fluctuation amplitudes, and current impact intensities of the regional power grid, calculates the occurrence frequency of regional power grid faults per unit time, and obtains the regional power grid fault characteristic data;

[0084] Based on the relay protection maloperation propagation data, it is necessary to first confirm the data source and integrity. Usually, the historical data of relay protection maloperations recorded by regional power grid monitoring equipment is used, and data supplementation is carried out in combination with the logs of the power dispatching system. In the example, a certain power grid area can be selected, and all the records of relay protection maloperations are collected within a week, and it is ensured that the data contains information such as trigger time, current and voltage fluctuation conditions, etc. Then, collect the short-time fault trigger times of the regional power grid. Short-time faults can be defined as fault events in the power grid with a duration less than 200 ms but causing fluctuations in the power grid, such as short-time overvoltage or short-time undervoltage. The occurrence times of such fault events are extracted from the event records of the monitoring equipment and the data is sorted out. When calculating, the short-time fault trigger times within a day can be summarized. For example, if the short-time fault trigger times are monitored to be 10 times in a certain period, this data is used as one of the analysis bases. Subsequently, collect the voltage fluctuation amplitude. The voltage fluctuation amplitude refers to the maximum change amplitude of the voltage before and after the fault, and can be calculated by the formula

[0085] ;

[0086] Among them, represents the steady-state voltage after the fault, represents the voltage before the fault occurs. If the voltage before the fault is monitored at 220 kV in a certain regional power grid and drops to 210 kV after the fault, the voltage fluctuation amplitude is 10 kV. Then, the current impact intensity is collected. The current impact intensity refers to the maximum change rate of the current immediately after the fault occurs, that is, the degree of sudden change of the current per unit time, and can be calculated as:

[0087] ;

[0088] Among them, represents the current before the fault, represents the maximum current after the fault, represents the measurement time interval. If the current before the fault in a certain power grid area is 500 A and rises to 1000 A immediately after the fault, and the measurement time interval is 0.1 s, then the current impact intensity is:

[0089] ;

[0090] Finally, calculate the fault occurrence frequency of the regional power grid per unit time. The number of fault triggers can be statistically counted within a certain time window and normalized. For example, if the statistical duration is set to 1 hour and the number of fault triggers monitored within 1 hour is 30 times, then the fault occurrence frequency is:

[0091] ;

[0092] Finally, the fault characteristic data of the regional power grid are obtained, including data sets such as the number of fault triggers, voltage fluctuation amplitude, current impact intensity, and fault occurrence frequency per unit time.

[0093] The regional fault risk calculation sub-module calls the fault characteristic data of the regional power grid and calculates the regional power grid fault risk score based on the fault incidence rate, voltage stability, and current impact characteristics. The formula is used:

[0094] ;

[0095] Calculate the regional power grid fault risk score , and obtain the regional power grid fault risk assessment result. Among them, represents the number of fault occurrences in the i-th time period, represents the unit time length, represents the voltage value in the i-th time period, represents the reference voltage value, represents the current impact intensity in the i-th time period, represents the total number of calculation time periods;

[0096] Call the fault feature data of the regional power grid, analyze the fault incidence rate, voltage stability, and current impact characteristics, and calculate the fault risk score of the regional power grid. First, the calculation method of the fault incidence rate can adopt the proportion of the number of faults, that is:

[0097] ;

[0098] Among them, represents the fault incidence rate, is the cumulative number of faults within the set time period, is the statistical duration. If a regional power grid has 120 short-term faults within 24 hours, the calculation of the fault incidence rate is:

[0099] ;

[0100] The analysis of voltage stability needs to calculate the voltage deviation based on the historical voltage fluctuation amplitude, and the deviation is calculated as:

[0101] ;

[0102] Among them, represents the average voltage within the set statistical time period, is the standard voltage of the power grid. For example, if the average voltage of a regional power grid in a day is 215 kV and the reference voltage is 220 kV, the calculation of the voltage deviation is:

[0103] ;

[0104] The calculation of the current impact characteristic is based on the maximum current mutation rate per unit time. For example, if the set calculation time period is 5 minutes and the maximum current mutation rate within this time period is 4000 A / s, it can be used for subsequent risk score calculation. Finally, based on the fault incidence rate, voltage stability, and current impact characteristic, calculate the fault risk score of the regional power grid, and use formula operations to obtain the fault risk score of the regional power grid and get the fault risk assessment value of the regional power grid.

[0105] Suppose a power grid area monitors 3 time periods, and the data is as follows: , , , , substitute into the calculation:

[0106] ;

[0107] Finally, the calculated fault risk assessment value of the regional power grid is 10545.0546.

[0108] The regional fault risk classification sub-module screens the risk regions with fault risk scores higher than the set risk threshold according to the regional power grid fault risk assessment results, marks them as high-risk regions, and generates the regional fault risk classification results;

[0109] Call the regional power grid fault risk assessment value, screen the high-risk regions with fault risk scores higher than the set risk threshold, set the risk threshold to 10000, and judge that 10545.0546 > 10000. Therefore, this region is divided and marked as a high-risk region, and then the regional fault risk classification results are generated.

[0110] Please refer to Figure 4 , the maloperation cumulative effect calculation module includes a relay protection maloperation cumulative trend calculation sub-module, a relay protection maloperation cumulative intensity calculation sub-module, and a relay protection maloperation high-risk screening sub-module;

[0111] The relay protection maloperation cumulative trend calculation sub-module extracts the maloperation trigger frequency of the relay protection device based on the relay protection maloperation propagation data and the regional fault risk classification results, calculates the cumulative change of the maloperation frequency in the time dimension, and obtains the relay protection maloperation cumulative trend record;

[0112] Based on the relay protection maloperation propagation data and the regional fault risk classification results, first, it is necessary to determine the maloperation propagation situation of the relay protection device. By monitoring the time sequence distribution of the relay protection maloperation in the region, the maloperation trigger frequency in different time periods is obtained. Assume that the number of maloperations of the relay protection device in a certain region within 24 hours is times, and the maloperation distribution in each hour is uneven. The maloperation frequency is relatively high in some periods. It is necessary to split the number of maloperations according to time periods. Assume that the maloperation occurs times from 8:00 to 12:00, the maloperation occurs times from 12:00 to 16:00, the maloperation occurs times from 16:00 to 20:00, and the maloperation occurs times from 20:00 to 24:00. By calculating the average maloperation trigger frequency per hour , the maloperation trigger frequency distribution in different time periods is obtained, so as to analyze the cumulative trend of maloperation in the time dimension; at the same time, the influence range of the maloperation also needs to be evaluated in combination with the regional fault risk classification results to determine whether there is a relatively dense propagation of maloperation in some time periods or regions. Taking a specific example, if the maloperation is triggered 50 times in region A within 24 hours and 10 times in region B within 24 hours, then the cumulative trend of maloperation in region A is significantly faster. It is necessary to further decompose whether there is a propagation relationship between regions in the source of the maloperation trigger. By collecting data to establish a maloperation propagation link, the relay protection maloperation cumulative trend record is finally obtained.

[0113] The cumulative strength calculation sub-module of relay protection maloperation calculates according to the cumulative trend of relay protection maloperation, using the formula:

[0114] ;

[0115] Calculate the cumulative strength of relay protection device maloperation , and obtain the cumulative strength data of relay protection maloperation. Among them, represents the maloperation trigger frequency in the th time period, represents the unit time interval, represents the maloperation propagation influence degree in the th time period, represents the average maloperation propagation influence degree of all time periods, represents the maloperation influence factor of the th relay protection device within the time period, represents the weight factor of the relay protection device, represents the total number of relay protection devices, represents the total number of calculation time periods;

[0116] Call the record of the cumulative trend of relay protection maloperation, calculate the cumulative strength of relay protection device maloperation, set the calculation unit time interval to 4 hours, and the maloperation trigger frequency to 5 times per hour. Then hours, times / hour, times / hour, times / hour, times / hour, and cumulatively calculate the maloperation strength component. If the maloperation propagation influence degree of relay protection devices in the region within the time period is 1.2 on average, then the regional average influence degree is set to 1.2, and the maloperation strength term is obtained through calculation. represents the device weight factor. For 4 main relay protection devices, within the set time interval of 4 hours (here a takes the value of 1, representing one time period), set , , , , represents the maloperation propagation influence, and the values are 1.5, 1.2, 1.8, and 1.0 respectively. Substitute into the formula, then the calculation of the maloperation propagation cumulative term is as follows. Substitute the values:

[0117] ;

[0118] Finally, calculate the cumulative strength of maloperation , obtain the cumulative intensity data of relay protection malfunctions. The results show that when the value is relatively large, the cumulative effect of relay protection malfunctions in this area is strong, and further measures need to be taken to reduce the propagation path of malfunctions and lower the triggering frequency of malfunctions.

[0119] The high-risk screening sub-module for relay protection malfunctions, based on the cumulative intensity data of relay protection malfunctions, screens relay protection devices whose cumulative intensity of malfunctions exceeds the set cumulative threshold, and generates a list of high-risk devices for relay protection malfunctions;

[0120] According to the cumulative intensity data of relay protection malfunctions, screen relay protection devices whose cumulative intensity of malfunctions exceeds the set cumulative threshold. The set cumulative threshold is 2. When the calculated value is greater than this threshold, it is considered that the malfunction intensity of this relay protection device is too high and needs to be included in the high-risk list. The calculated cumulative intensity value of malfunctions in this area for 24 hours is 2.26, which is greater than the cumulative threshold of 2. Then the relay protection devices in this area enter the high-risk device list for malfunctions. If the calculated cumulative intensity value of malfunctions in another area is 1.95, which is less than the cumulative threshold of 2, then this area is not included in the high-risk range. Finally, a list of high-risk devices for relay protection malfunctions is obtained through screening.

[0121] Please refer to Figure 5 , the protection level adjustment module includes a relay protection device adjustment factor calculation sub-module, a relay protection device adjustment and screening sub-module, and a relay protection device level setting sub-module;

[0122] The relay protection device adjustment factor calculation sub-module, based on the cumulative intensity data of relay protection malfunctions and the regional fault risk classification results, uses the formula:

[0123] ;

[0124] Calculate the protection level adjustment factor of the relay protection device , and obtain the relay protection device adjustment factor data. Among them, represents the cumulative intensity of malfunctions in the th time period, represents the unit time length, represents the regional fault risk score in the th time period, represents the median regional fault risk score of all time periods, represents the voltage fluctuation amplitude of the th relay protection device within the time period, represents the reference voltage fluctuation amplitude, represents the weight factor of the relay protection device, represents the total number of relay protection devices, Represents the total number of calculation time periods, Is a small constant to prevent the denominator from being zero;

[0125] Based on the cumulative intensity data of relay protection misoperations and the results of regional fault risk classification, the relay protection device adjustment factor calculation sub-module needs to first extract the cumulative intensity of misoperations and the regional fault risk scores of each relay protection device in different time periods. In actual applications, the relay protection devices in a certain power region may reduce the system reliability due to long-term misoperations. For example, the protection device of a substation misoperated 3 times in the past 24 hours, while that of another substation only misoperated 1 time. At this time, it is necessary to calculate the cumulative intensity of misoperations of each device to evaluate its impact. First, record the cumulative intensity of misoperations of each relay protection device , for example, the misoperation intensity of device A in the past week is times, and that of device B is times, and so on. Next, calculate the regional fault risk score within this time period . Suppose the overall fault risk scores of a certain regional power grid in different time periods are respectively , , . Calculate its average value to ensure the representativeness of the data distribution. The average value is calculated as:

[0126] ;

[0127] Then, calculate the voltage fluctuation amplitude of each device in different time periods , such as the voltage fluctuation values of a certain substation in different time periods are , , . At the same time, determine the reference voltage fluctuation , for example, the reference voltage fluctuation value stipulated by the industry standard is . Calculate the protection level adjustment factor of each device based on these data.

[0128] Among them, : The cumulative intensity of misoperations in the th time period (such as device A misoperated 8 times in the past week), : The unit time interval (such as 7 days), : The regional fault risk score in the th time period (such as 6.2), : The median of the regional fault risk scores in all time periods (such as 6.37), : A small constant to prevent the denominator from being zero (such as 0.01), : The The voltage fluctuation amplitude of a relay protection device (e.g., 3.5%, which means that only one relay protection device has a voltage fluctuation amplitude within 3 time periods), : The reference voltage fluctuation amplitude (e.g., 3.0%), : The weight factor of the relay protection device (e.g., the weight of the main transformer protection device is 1.5), : The total number of relay protection devices (e.g., 1 device), : The total number of calculation time periods (3 time periods).

[0129] Substitute the values into the calculation:

[0130] ;

[0131] It is calculated that the protection level adjustment factor of this relay protection device is , and the adjustment threshold is set to 1.0. Then, the adjustment factor of this device is greater than the threshold, and the protection level needs to be adjusted.

[0132] The relay protection device adjustment and screening sub-module screens the relay protection devices whose protection level adjustment factors exceed the set adjustment threshold according to the relay protection device adjustment factor data, and obtains the relay protection device adjustment list;

[0133] The relay protection device adjustment and screening sub-module calls the relay protection device adjustment factor data to screen the relay protection devices whose protection level adjustment factors exceed the set adjustment threshold. In actual application, the grid operation and maintenance personnel will set the adjustment threshold , for example, if , then all adjustment factors greater than 0.9 need to be screened for adjustment. The calculated adjustment factor data is as follows:

[0134] Table 1 Calculation data

[0135]

[0136] Based on the adjustment threshold , according to Table 1, all devices with adjustment factors greater than 0.9 are screened out, that is, X1, X2, and X4 need to have their protection levels adjusted, while X3 does not need to be adjusted because its adjustment factor is lower than 0.9. In actual operation, the screened devices will be marked, included in the subsequent adjustment process, and a list of devices to be adjusted will be generated to obtain the relay protection device adjustment list.

[0137] The relay protection device level setting sub-module adjusts the protection levels of the corresponding relay protection devices based on the relay protection device adjustment list, and generates the set result of the relay protection level after adjustment;

[0138] The relay protection device level setting sub-module calls the relay protection device adjustment list to perform protection level adjustment on the selected relay protection devices. Generally, the protection level adjustment involves changing the setting parameters of the relay protection device, such as the fault current threshold, voltage threshold, delayed protection time, etc. In the specific implementation process, assume that devices X1, X2, and X4 need to be adjusted, and the adjustment methods include:

[0139] Adjust the protection setting value:

[0140] Device X1 (substation main transformer protection device)

[0141] Original setting value: Short-circuit current protection setting value , delay 0.2s

[0142] After adjustment: , delay 0.25s

[0143] Device X2 (transmission line protection device)

[0144] Original setting value: Voltage lower limit protection , time delay 0.3s

[0145] After adjustment: , time delay 0.35s

[0146] Device X4 (section switch protection device)

[0147] Original setting value: Tripping current threshold

[0148] After adjustment:

[0149] Assume that the existing fault current detection value of device X1 is , the original protection setting value , and the misoperation frequency is relatively high. Therefore, it is necessary to increase the protection setting value to to reduce misoperation, and calculate the adjustment range of the protection level: , and the adjustment range of the delayed protection time is calculated as follows: , the calculation shows that the protection level will be increased after adjustment, so that device X1 will trigger protection only when the fault current reaches 1600A and delay 0.05s to execute tripping. In the power dispatching system, the adjustment parameters can be configured through the remote background system. For example, the SCADA system can directly push the new protection setting value to the device, or it can be manually adjusted by on-site maintenance personnel. All adjustment data will be recorded in the power equipment management system, and the relay protection level setting result after adjustment will be generated. Finally, the adjusted data will be applied to the relay protection equipment to ensure the rationality of the protection level.

[0150] Please refer to Figure 6, the fault response module includes a relay protection adjustment sub-module, a regional power grid status calculation sub-module, and a power grid stability optimization sub-module;

[0151] Based on the set result of the relay protection level after adjustment, the relay protection adjustment sub-module records the protection action time, setting value, and tripping threshold value after adjustment, compares the change range of the relay protection action time before and after adjustment, screens the key relay protection adjustment points, calls the key relay protection adjustment points to match with the protection fault data, calculates the deviation of the relay protection response duration after adjustment, and obtains the relay protection response deviation amount;

[0152] When extracting relay protection parameters based on the set result of the relay protection level after adjustment, first obtain the action time, setting value, and tripping threshold value of the relay protection device before and after adjustment. The parameters can be extracted through the real-time monitoring data of the dispatching system and the historical records of the protection device. For example, if the action time of a certain protection device before adjustment is 0.3s and after adjustment is 0.25s, then the action time is reduced by 0.05s. The adjustment range of the setting value and tripping threshold value can be calculated by comparing the setting values of the protection device in different time periods. Select the key relay protection adjustment point with the largest change range, and call the corresponding historical protection fault data of this adjustment point for matching. For example, in the past year, this device has tripped 10 times, and the fault type, fault time, and protection device response situation each time can be used as the matching basis. By matching the fault data and the relay protection setting value after adjustment, the deviation of the relay protection response duration after adjustment can be calculated. The calculation method is the response time after adjustment minus the response time before adjustment. For example, if the average response time before adjustment is 0.3s and after adjustment is 0.25s, then the deviation is -0.05s. This deviation value can be used to evaluate the impact of relay protection adjustment on fault response, and finally obtain the relay protection response deviation amount.

[0153] Based on the relay protection response deviation amount, the regional power grid status calculation sub-module combines the voltage stability, frequency fluctuation range, and load transfer efficiency, compares the change trends of the power grid operation parameters before and after adjustment, and uses the formula:

[0154] ;

[0155] Calculate the change amount of the power grid operation state , compare the change intervals of the operation parameters before and after adjustment, and obtain the power grid operation state parameters after adjustment. Among them, represents the voltage value at time i after adjustment, represents the voltage value at time i-1 before adjustment, represents the relay protection response time at time i, represents the active power at time i after adjustment, represents the reactive power at time i after adjustment, represents the frequency at adjusted time i, represents the reference frequency, represents the total number of calculation time periods;

[0156] When calculating the operation parameters of the regional power grid based on the relay protection response deviation, first extract the voltage stability, frequency fluctuation range, and load transfer efficiency. These parameters can be obtained from the power grid operation monitoring data. For example, the voltage stability can be determined by calculating the deviation value of the voltage fluctuation range from the reference voltage. Assuming the reference voltage at a certain moment is 220 kV, and the actual voltage fluctuation range after adjustment is ±5 kV, then the voltage stability is , the frequency fluctuation range can be calculated by comparing the frequency values before and after adjustment. For example, the frequency range within a certain time period before adjustment is from 49.8 Hz to 50.2 Hz, and after adjustment it is from 49.85 Hz to 50.15 Hz, then the fluctuation amplitude is reduced by 0.05 Hz. The load transfer efficiency can be calculated by the ratio of active power to reactive power. Assuming the active power at a certain moment after adjustment is 500 MW and the reactive power is 200 Mvar, then the load transfer efficiency is , based on the calculation results, use formula operations to obtain the change amount of the power grid operation state, and compare the change intervals of the operation parameters before and after adjustment. For example, the change amount of the power grid operation state within a certain time period before adjustment is 0.8, and after adjustment it is 0.6, which indicates that the power grid operation state tends to be stable, and finally obtain the power grid operation state parameters after adjustment.

[0157] Among them, represents the voltage value at adjusted time i, which is 219 kV, represents the voltage value at time i - 1 before adjustment, which is 220 kV, represents the relay protection response time at time i, which is 0.25 s, represents the active power at adjusted time i, which is 500 MW, represents the reactive power at adjusted time i, which is 200 Mvar, represents the frequency at adjusted time i, which is 49.85 Hz, represents the reference frequency, taking 50 Hz, represents the number of time slices within the calculation period, which is 10.

[0158] Assume that the data of 10 time slices are consistent, and substitute the data for calculation:

[0159]

[0160] The results show that the power grid operation state parameters after adjustment are more stable than those before adjustment and can be used to further optimize the relay protection strategy.

[0161] Based on the adjusted power grid operation state parameters, the power grid stability optimization sub-module calculates the changing trend of power grid stability, screens the key factors of operation state changes, optimizes the relay protection adjustment strategy, adjusts the relay protection level setting, corrects the relay protection tripping threshold, and establishes a dynamic response plan for the power grid relay protection;

[0162] When calculating the changing trend of power grid stability based on the adjusted power grid operation state parameters, first analyze the changes in the adjusted operation parameters and screen the key factors of operation state changes. For example, by comparing the power grid voltage stability, frequency fluctuation range, and load transfer efficiency before and after the adjustment, determine which parameter changes are the most obvious. For example, if the voltage stability during a certain period before the adjustment is 3% and it becomes 2.27% after the adjustment, it indicates that the voltage fluctuation range has converged. After screening out the key influencing factors, optimize the relay protection adjustment strategy and adjust the relay protection level setting. For example, for areas with a large voltage fluctuation range, appropriately increase the relay protection setting value, and for areas with a small frequency fluctuation, reduce the tripping threshold value to optimize the relay protection adjustment strategy. During the execution process, it is necessary to calculate the changing trend of power grid stability before and after the adjustment based on the data of the power grid operation state change amount. For example, the power grid stability change amount before the adjustment is 0.8 and it becomes 0.6 after the adjustment. Finally, establish a dynamic response plan for the power grid relay protection.

[0163] The above are only the preferred embodiments of the present invention, and do not limit the present invention in other forms. Any person skilled in the art may use the disclosed technical content to make changes or modifications into equivalent embodiments with equivalent changes and apply them to other fields. However, as long as it does not depart from the technical solution content of the present invention, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A relay protection fault identification and response system, characterized in that: The system comprises: The fault propagation path tracing module collects relay protection device data, records the triggering sequence of relay protection devices, calculates the triggering interval time, analyzes the false operation propagation path, calculates the correlation strength of cascade false operation, determines the cascade false operation and classifies the devices, and generates relay protection false operation propagation data; The regional fault monitoring module obtains regional power grid data based on the relay protection misoperation propagation data, calculates the frequency of regional power grid faults, and generates regional fault risk classification results; The misoperation cumulative effect calculation module calculates the cumulative trend of relay protection misoperation according to the relay protection misoperation propagation data and the regional fault risk classification result, extracts the misoperation triggering frequency, and outputs the relay protection misoperation cumulative intensity data; The protection level adjustment module calculates the protection level adjustment factor of the relay protection device according to the cumulative intensity data of the relay protection misoperation and the regional fault risk classification result, and generates the adjusted relay protection level setting result; The fault response module calculates the regional power grid operation status parameters based on the adjusted relay protection level setting result, dynamically optimizes the relay protection adjustment measures, and generates a power grid relay protection dynamic response plan; The misoperation cumulative effect calculation module includes a relay protection misoperation cumulative trend calculation submodule, a relay protection misoperation cumulative intensity calculation submodule, and a relay protection misoperation high risk screening submodule; The relay protection misoperation cumulative trend calculation submodule determines the misoperation propagation of the relay protection device based on the relay protection misoperation propagation data and the regional fault risk classification result, monitors the time distribution of the relay protection misoperation in the region, extracts the misoperation triggering frequency of the relay protection device, calculates the cumulative change of the misoperation frequency in the time dimension, analyzes the cumulative trend of the misoperation in the time dimension, and obtains the cumulative trend record of the relay protection misoperation; The relay protection misoperation cumulative intensity calculation submodule uses the formula: ； Calculation of cumulative strength of false operation of relay protection devices , get the cumulative intensity data of relay protection misoperation, where, Representative The false trigger frequency of each time period, Represents the unit time interval, Representative The influence of false operation propagation in each time period, Represents the average false operation propagation impact of all time periods, Representative In the time period The influencing factor of the false operation of a relay protection device is represents the weight factor of the relay protection device, Represents the total number of relay protection devices, Represents the total number of calculation periods; The relay protection malfunction high-risk screening submodule screens relay protection devices whose malfunction cumulative intensity exceeds a set cumulative threshold based on the relay protection malfunction cumulative intensity data, and generates a list of relay protection malfunction high-risk devices.

2. The relay protection fault identification and response system according to claim 1, characterized in that: The relay protection misoperation propagation data includes relay protection device triggering time record, current mutation rate record, voltage drop rate record, relay protection device triggering sequence, relay protection device triggering interval time, cascade misoperation correlation strength, relay protection misoperation triggering frequency, misoperation cumulative impact value classification result, and relay protection misoperation propagation path; the regional fault risk classification result includes regional power grid short-term fault triggering statistics, voltage fluctuation amplitude distribution, current impact intensity distribution, fault occurrence frequency per unit time, regional power grid fault risk score, and high-risk area screening results; The relay protection misoperation cumulative intensity data includes the relay protection misoperation cumulative trend, the relay protection device misoperation trigger frequency statistics, the relay protection device misoperation cumulative intensity, and the misoperation high risk device screening results; The adjusted relay protection level setting result includes the protection level adjustment factor of the relay protection device, the protection level adjustment determination result of the relay protection device, and the protection level of the relay protection device after adjustment; The grid relay protection dynamic response plan specifically refers to the adjusted regional grid operation status parameters, regional grid operation stability difference analysis records, and relay protection adjustment measure optimization plan.

3. The relay protection fault identification and response system according to claim 1, characterized in that: The fault propagation path tracing module includes a relay protection device triggering data collection submodule, a relay protection malfunction propagation analysis submodule, and a relay protection malfunction impact assessment submodule; The relay protection device triggering data collection submodule collects the current mutation rate and voltage drop rate according to the triggering time of the relay protection device, records the triggering sequence of the relay protection device, calculates the interval time between the triggering of adjacent relay protection devices, and obtains the triggering timing data of the relay protection device; The relay protection malfunction propagation analysis submodule analyzes the relay protection malfunction propagation path according to the relay protection device triggering timing data, and selects the relay protection device whose triggering interval time is less than the set triggering threshold, using the formula: ； Calculate the correlation strength of cascaded false actions , and judge the cascade misoperation to obtain the cascade misoperation propagation sequence, where Represents relay protection device The triggering moment, Represents relay protection device The triggering moment, Represents setting the trigger threshold. Represents the total number of devices in the relay protection device triggering sequence; The relay protection false operation impact assessment submodule calculates the relay protection false operation triggering frequency according to the cascade false operation propagation sequence, classifies the devices according to the false operation cumulative impact value, screens the relay protection devices whose false operation cumulative impact value exceeds the set interval, and generates relay protection false operation propagation data.

4. The relay protection fault identification and response system according to claim 1, characterized in that: The regional fault monitoring module includes a power grid fault data collection submodule, a regional fault risk calculation submodule, and a regional fault risk classification submodule; The power grid fault data collection submodule collects the number of short-term fault triggering times, voltage fluctuation amplitude, and current impact intensity of the regional power grid based on the relay protection malfunction propagation data, calculates the frequency of regional power grid faults per unit time, and obtains regional power grid fault characteristic data; The regional fault risk calculation submodule calls the regional power grid fault characteristic data, and calculates the regional power grid fault risk score based on the fault occurrence rate, voltage stability, and current impact characteristics, using the formula: ； Calculating regional grid failure risk scores , and obtain the regional power grid failure risk assessment results, where: represents the number of failures in the i-th time period, Represents the unit time length, represents the voltage value of the i-th period, Represents the reference voltage value, represents the current impulse intensity in the ith period, Represents the total number of calculation periods; The regional fault risk classification submodule screens risk areas with fault risk scores higher than a set risk threshold according to the regional power grid fault risk assessment results, marks them as high-risk areas, and generates regional fault risk classification results.

5. The relay protection fault identification and response system according to claim 1, characterized in that: The protection level adjustment module includes a relay protection device adjustment factor calculation submodule, a relay protection device adjustment screening submodule, and a relay protection device level setting submodule; The relay protection device adjustment factor calculation submodule adopts the formula based on the cumulative intensity data of relay protection misoperation and the regional fault risk classification result: ； Calculate the protection level adjustment factor of relay protection device , get the relay protection device adjustment factor data, where, Representative The cumulative intensity of false operation in a time period, Represents the unit time length, Representative The regional failure risk score for each time period, represents the median regional failure risk score for all time periods, Representative In the time period The voltage fluctuation amplitude of each relay protection device, Represents the reference voltage fluctuation amplitude, represents the weight factor of the relay protection device, Represents the total number of relay protection devices, represents the total number of computation periods, To prevent a small constant with a zero denominator; The relay protection device adjustment screening submodule screens the relay protection devices whose protection level adjustment factors exceed the set adjustment threshold according to the relay protection device adjustment factor data, and obtains a relay protection device adjustment list; The relay protection device level setting submodule adjusts the protection level of the corresponding relay protection device based on the relay protection device adjustment list and generates an adjusted relay protection level setting result.

6. The relay protection fault identification and response system according to claim 1, characterized in that: The fault response module includes a relay protection adjustment submodule, a regional power grid state calculation submodule, and a power grid stability optimization submodule; The relay protection adjustment submodule records the adjusted protection action time, setting value and tripping threshold value based on the adjusted relay protection level setting result, compares the change range of the relay protection action time before and after the adjustment, selects the key relay protection adjustment point, calls the key relay protection adjustment point and matches the protection fault data, calculates the adjusted relay protection response time deviation, and obtains the relay protection response deviation; The regional power grid state calculation submodule is based on the relay protection response deviation, combined with voltage stability, frequency fluctuation range and load transfer efficiency, and compares the change trend of power grid operation parameters before and after adjustment, using the formula: ； Calculate the change in power grid operation status , compare the change range of the operating parameters before and after the adjustment, and obtain the adjusted power grid operating state parameters, among which, represents the voltage value at time i after adjustment, represents the voltage value at time i-1 before adjustment, Represents the relay protection response time at time i, represents the active power at time i after adjustment, represents the reactive power at time i after adjustment, represents the frequency at time i after adjustment, represents the base frequency, Represents the total number of calculation periods; The grid stability optimization submodule calculates the grid stability change trend, screens key operating state change factors, optimizes the relay protection adjustment strategy, adjusts the relay protection level setting, corrects the relay protection tripping threshold, and establishes a grid relay protection dynamic response plan based on the adjusted grid operating state parameters.

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